Explosion-proof liquid fuel pump

ABSTRACT

A double acting piston type liquid fuel pump is driven by an integrally constructed coaxial flexible-diaphragm gas piston within a dual compartment chamber. The compartments are alternately connected to a vacuum or pressure source through a reversible toggle valve operated by movements of the diaphragm.

United States Patent 1151 3,700,359 Vanderjagt Oct. 24, 1972 [54]EXPLOSION-PROOF LIQUID FUEL [56] References Cited PUMP UNITED STATESPATENTS [721 Invent: 1,830,257 11/1931 Bohnenblust ..417/52s x Tenn-2,636,701 4/1953 Minshell et a1. ..91/345 X [73] Assignee: Science,Inc., Memphis, Te 2,887,955 5/1959 Ovven ..4l7/404 3,151,805 10/1964Pnbenic ..91/345 X [22] Filed: May 18, 1971 Primary Examiner-Carlton R.Croyle APPL 4548 Assistant Examiner-Richard E. Gluck J's. pp i mAttorneyBuckles and Bramblett [63] Continuation-impart of Ser. No.23,866, March [57] 7 ABSTRACT 1970 abandoned A double acting piston typeliquid fuel pump is driven by an integrally constructed coaxialflexible- [52] US. Cl. ..417/404, 91/345, 417/528 diaphragm gas pistonwithin a dual compartment [51 1 Int. chamber. The ompartments arealtemately con- [58] Field of Search ..4l7/404, 528; 91/345 nected to avacuum or pressure source through a reversible toggle valve operated bymovements of the diaphragm.

14 Claims, 7 Drawing Figures PATENTED 24 I97? 3. 700 359 sum 1 or 3 39I4 38 I INVENTOR. 34 32 4/ 40 37 O k n fl. Velma 2747i QM a. @M,

AT TORNF Y PATENTEnum 24 1972 SHEET 3 BF 3 0 K W H n M f IMIT-BACKGROUND or THE INVENTION This application is a continuation-in-partof my copending application Ser. No. 23,866, now abandoned, filed Mar.30, 1970 for Explosion-Proof Liquid Fuel Pump.

In the heavy construction and road building industries which use fossilfueled machines such as power shovels, back-hoes, bulldozers, cranes,etc., as well as in farming with tractors, harvesters and the like, itis necessary to fuel such machines in the field where the work isunderway, as it is wholly impractical to drive the machines to a centralfuel depot or filling station. Accordingly, all such equipment usersmust have a fuel delivery truck capable of refueling these machines onlocation in the field. Large fuel tank trucks as em ployed by the oilcompanies hold much more fuel than is ordinarily required for the farmeror contractors day-to-day operations, and they are uneconomical for asmall operator to own and maintain. Consequently most contractors andfarmers use a small truck, such as a pick-up truck, in which they carryone or 'more 50 gallon barrles of fuel around to their various machinesfor refueling once or twice a day, as may need be. Because constructionand farm workers have sometimes been known to syphon off fuel into theirown personal automobiles when the boss is not around, most contractorsseek to supply each construction machine with only enough fuel for onedays operation. The simplest way to transfer fuel from these fiftygallon drums into a working machine in the field is by means of a handpump, but this is laborious and time consuming. Small electrical pumpshave been proposed for this purpose but they pose the danger of fire orexplosion from an electrical spark, and therefore they are not approvedby Underwriters. Pumps driven by power take off from the rotating shaftof the truck engine, as employed in the large tank trucks of the oilcompanies, are impractical for most farmers or contractors because theyrequire costly modification of the truck engine and drive mechanism.

OBJECTS OF THE INVENTION liquid pump operable from a vacuum line.

Another object is to provide such a pump operable from a pressurized airsource.

Another object is to provide a liquid pump which automatically stopsoperating when there is no further call for liquid, without requiring acut-off switch control.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the features of construction,combination of elements, and arrangement of parts whichwill beexemplified in the construction hereinafter set forth, and the scope ofthe invention will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention,reference should be had to the followingdetailed description taken inconnection with the accompanying drawings in which:

FIG. 1 is a vertical crosssectional view of one embodiment of a pump ofthe invention;

FIG. 2 is a top view, partially in section, of the vacuum control valvetaken along the line 2-2 of FIG.

FIG. 3 is a vertical cross-sectional view of a modified form of theinvention;

line 5-5 of FIG. 3;

FIG. 6 is a front view of a pressure regulator usable with the pump ofthe invention; and

FIG. 7 is a cross-section taken substantially along the line 7-7 of FIG.6.

BRIEF DESCRIPTION OF THEINVENTION In general the pump of the inventioncomprises a double acting piston pump having integrally joinedtherewith, by a common reciprocating piston shaft, a double actingdiaphragm motor adapted for connection to either a source of compressedair or the vacuum system of an internal combustion engine in a truck orother automotive vehicle. A toggle valve on the device is operated bythe reciprocating diaphragm to alternately apply vacuum or pressure toopposite sides of the diaphragm whereby the piston shaft is caused toreciprocate. A liquid intake port of the pump includes a threaded nippleextension adapted to screw into a bung hole in the top of a gasolinedrum. A flat linear portion is machine cut into the external threadedsurface of the intake nipple to provide an air vent into the drumthrough the bung hole. lntemal threads within the intake nipple receivea short length of threaded pipe which extends downwardly into proximitywith the bottom of the fuel drum so that substantially the entire liquidcontents of the drum can be removed by the pump.

Motion of the reciprocating pump piston on the up stroke creates vacuumat the liquid intake port thereby drawing fuel upwardly through a firstflap valve into the lower portion of the pump cylinder. On the downstrike of the pump piston the first flap valve closes under the pressureof liquid thereabove while a second flap valve opens to partiallyrelieve this pressure and to admit liquid into the upper portion of thepump cylinder, above the piston. At the same time, during the downstroke of the pump piston, a spring loaded liquid release valve in thecylinder wall below the piston is opened by the remaining fluid pressureand allows excess liquid to pass'through an exhaust passage to a liquiddischarge port. After a very few reciprocating cycles of the piston theentire internal volume of the pumping cylinder, both above and below thepiston, becomes filled with liquid and the pump is fully primed. Onsucceeding strokes of the piston liquid is alternately passed through anupper spring loaded release valve I tomatic) shut off valve at thedelivery nozzle of the hose, the fuel tanks of machines in the field caneasily be supplied with any desired amount of gasoline. When the shutoff valve at the delivery nozzle is closed the pump stops due to theback up of pressure in the pumping cylinder, and there is no need tooperate a separate switch or other control to turn off the pump. As soonas the delivery nozzle is again opened the pump resumes operating todeliver a steady flow of liquid fuel.

DETAILED DESCRIPTION Referring now in greater detail to FIG. 1 of thedrawing, which is a vertical cross-sectional view of one embodiment ofthe device, the structural arrangement of parts and the combination ofelements which comprise the invention will be described. A flexible airhose 5 is connected to the air intake, or vacuum line, of an internalcombustion engine (not shown). The vacuum hose 5 connects through a dualport toggle valve, indicated generally at 6 in FIG. 1, to alternatesides of a vacuum cylinder indicated generally at 7. Vacuum cylinder 7is enclosed by an upper annular wall 8 and a corresponding lower annularwall 9 with a flexible diaphragm 10 securely clamped between outerperipheral edges 11 and 12 of walls 8 and 9, respectively. A verticalpiston shaft 14 passes through a central bearing 15 in the upper wall 8and is hermetically sealed by an O ring 16 therein. The piston shaft 14supports and carries a pair of rigid circular piston discs 17 and 18clampingly held in contact with opposite faces of flexible diaphragm 10by a locknut 19 tightened against an annular shoulder portion 20 of alarger diameter cylindrical lower extension 21,0f the piston shaft 14.The bottom wall 9 of vacuum cylinder 7 is secured to an upper bearingend 22 of a liquid pumping cylinder indicated generally at 24 in FIG. 1,and is further supported by brackets 25 and 26 also mounted on the pumpcylinder 24.

In the position shown in FIG. 1, vacuum from line 5 is applied throughport 27 of toggle valve 6 to the upper chamber 28 of vacuum cylinder 7,while the lower chamber 29 is connected through a flexible hose 30 toatmospheric pressure through open port 31 of toggle valve 6. In thisposition the piston shaft 14 has completed its down stroke and thevacuum applied to chamber 28 now causes the vacuum piston 17-18 sealedat its periphery by flexible diaphragm 19, to rise under the influenceof atmospheric pressure in chamber 29. As piston rod 14 rises it causesa rocker arm 32, driven by a pin 34 in rod 14 riding in slot 35 torotate about a supporting pivot pin 36 in valve 6, thereby compressing aspring 37 mounted between pivot 38 on valve cover 39 and pivot 40 on theend of rocker arm 32. Valve cover 39 is pivotally mounted on valve 6 bya pivot pin 41. As piston rod 14 approaches the upper limit of itstravel, rocker arm 32 reaches a horizontal position at which pin 34 andpivots 40, 41, and 36 are substantially aligned and spring 37 issubstantially fully compressed. A slight further upward motion of pistonrod 14 brings pivot 40 below this horizontal linear alignment whereuponspring 37 releases its compressed energy to rapidly swing its oppositeend, affixed to valve cover 39 by pivot 38, into its uppermost positionthereby rotating valve cover 39 about its pivot 41 to quickly open valveport 27 to atmospheric pressure and to connect valve port 31 to vacuumline 5. Now, with atmospheric pressure introduced into chamber 28 andthe vacuum applied to chamber 29, the piston 17-18, sealed by flexiblediaphragm l0, commences its downward stroke until it again reaches itslowest position and the snap acting valve member 39 of toggle valve 6returns to the position shown in FIG. 1. In this manner continuousvertical reciprocating motion is imparted to piston rod 14 and itsopposite enlarged end 21 which slides up and down in effect a hermeticsealing engagement with sliding shaft 21.

Reference is not had in greater detail to the construction and operationof the liquid pumping portion of the device indicated generally at 24 inFIG. 1. The dual acting pump cylinder 24 is formed of an uppercylindrical casting 44 securely joined to a lower east part 45 enclosingtherebetween dual pumping chambers 46 and 47 which are separated by arigid cylindrical piston 48 having a piston ring 49 mounted in itsperiphery for maintaining intimate sealed contact with the innercylinder wall 50. Piston 48 is rigidly connected to the lower end 21 ofpiston shaft 14-21 by an annular disc 51 which is welded or braised ontothe shaft 21 and secured to the piston 48 by a plurality of machinescrews 52 passing through a corresponding plurality of spacers 54. Ahollow cylindrical tube 55 is mounted through a central coaxial openingin piston 48 and is secured thereto in a manner forming at its upper endan annular valve seat 56. A rigid valve disc 57 is seated in the annularrecess of valve seat 56 but is free to move upward therefrom under theinfluence of liquid pres sure. When valve disc 57 moves upwardly it isguided laterally by a slight clearance between its outer periphery andthe sidewalls of spacers 54. Valve disc 57 is also limited in its upwardtravel by an extension 58 on the lower end of piston shaft 21, theclearance between disc 57 and extension 58 being only sufficient toallow fluid to flow upwardly through hollow cylinder 55, around theperiphery of valve seat 56 and the periphery of raised disc 57, andthrough the space between spacers 54, in the direction shown by arrowsin FIG. 1.

Through the bottom wall 45 of pumping cylinder 24 a plurality ofopenings 59 are symmetrically positioned about the axis of piston rod14-21 and connect the chamber 47, beneath piston 48, with the lower andsmall cylindrical chamber 60 into which hollow cylinder 55 extends.Openings 59 are normally closed by an overlying annular valve washer 61which is loosely fitted around cylinder 55, as shown in FIG. 1. Thelower portion of chamber 60 is constricted into a smaller diameternipple portion 62 which is externally threaded to fit into a threadedbung hole 64 in the top of a fuel drum 65. The inner cylindrical wall 66of nipple portion 62 is threaded to receive the end of a threaded pipe67 which extends downwardly into proximity with the bottom (not shown)of fuel drum 65. Along one vertical portion of the exterior threadedsurface of nipple portion 62 a flat surface is milled to provide an airvent 68 between the nipple 62 and the bung hole 64 of drum 65. In theupper wall of cylinder casting 44 a fluid exit valve opening 69 isnormally closed by a spring loaded valve 70, while in the lower cylinderwall 45 a corresponding fluid exit valve opening 71 is normally closedby a spring loaded valve 72, as shown in FIG. 1. In operation the valveopenings 69 and 71 are alternately connected with'a common fluid exitchannel 74, as valves 70 and 72 are alternately opened. Fluid exitchannel 74 opens into a liquid exhaust port 75 to which is threadablyconnected a flexible fuel delivery hose 76. i

The operation of the pumping cylinder 24 is as follows: with the pumppiston 48 at the bottom of its down stroke, as shown in FIG. 1, thelifting force on piston shaft 14-21 produced by atmospheric pressure inchamber 29 and vacuum in chamber 28, as described hereinabove, causespiston 48 to rise into pump chamber 46, thereby creating vacuum in pumpchamber 47. Atmospheric pressure entering drum 65 through air vent 68forces liquid in the drum to rise through pipe 67 into fluid admittingchamber 60. As piston 48 continues to rise the fluid pressure in chamber60 lifts valve washer 61, which rides freely upwardly on the exteriorsurface of hollow cylinder 55 to admit liquid through openings 59 intothe expanding volume of chamber 47, between piston 48 and bottomcylinder wall 45. During the upstroke of piston 48 the valve disc 57remains seated in valve seat 56 to maintain the piston opening closed.Since the pumping apparatus of the invention is normally installed inavertical position as shown in FIG. 1, gravity holds the disc 57 in itsclosed positioneven at the start of a dry stroke when only air is in theupper chamber 46. However, if the device is to be operated in other thanthe vertical position shown, then a small compression spring (not shown)may be inserted around the extension and 58 of piston shaft 21 to springload the valve disc 57 into its closed position during the upstroke.

When piston 48 reaches the top of its upstroke the chamber 47'beneaththe piston is substantially filled with liquid. As thedownstroke of piston 48 commences, valve washer 61 is forced down byincreasing fluid pressure and closes openings 59. The fluid in chamber47 under pressure of the piston 48 downstroke now opens spring loadedvalve 72 which allows liquid to pass through valve opening 71, exitchannel 74 and exit port 75 into delivery hose 76. At the same time,during the downstroke of piston 48, the pressure of fluid previouslyaccumulated in chamber 60 lifts valve disc 57 allowing fluid to flowthrough hollow cylinder 55 and the open spaces between spacers 54 intothe upper pumping chamber 46. After only a very few strokes of piston 48the upper chamber 46 as well as the lower chamber 47 and the fluidadmitting chamber 60, are all completely filled with liquid from thedrum 65, and the pump 24 is fully primed. Now on each successiveupstroke fluid in chamber 46 is forced out through valve opening 69,while on each successive downstroke fluid in chamber 47 is forced outthrough valve opening 71, to produce a continuous flow of fluid throughexit channel 74 and exit port 75 into delivery hose 76.

If the fluid delivery hose 76 is closed at its opposite end by a liquidshut-off valve (not shown) then fluid pressure back-up on both sides ofpiston 48 will prevent furtheroperation of the pump 24-or of itsintegrally I the connected internal combustion engine from intake ofdust or other deleterious foreign matter along with the air intake, acover with an air filter (not shown) should be mounted over the togglevalve 6.

FIG. 2 of the drawing, which is a top cross-sectional view taken alongthe line 2-2 of FIG. 1, merely helps to clarify an understanding of theoperating relation between thevarious parts of the toggle valve 6, asexplained hereinabove with reference to FIG. 1 of the drawing. I

FIGS. 3-5 illustrate a modified form of the pump of this invention. Theprinciples of operation are basically the same as those previouslydescribed. Accordingly, a number of parts are also similar and, whereappropriate, they have been given the same reference numerals but with aprime attached. This modification is mechanically simplified and morecompact. As illustrated, the upper portion of the pumping cylinder 80defines a recess 81 within which is mounted a toggle valve 82. Thetoggle valve 82 is functionally similar 'to that previously describedand includes a pivoted valve cover 39' mounted on pivot 41'. In thisversion, the vacuum hose 5 is connected to the toggle valve in the samemanner. The upper port connects directly to chamber 29' through apassage 83 while the lower port is connected to chamber 28' by means ofahose 84. In this modification, the toggle valve is actuated by a pushrod 85 mounted directly on the diaphragm by means of a nut 86. The pushrod 85 reciprocates in a vertical bore 87 and carries a pin 88 whichextends outwardly through a slot 89 formed in the housing. An elastic Oring 90 interconnects the pin 88 on push rod 85 with a pin 91 on valvecover 39'. As pin 88 moves up and down in response to movement of thediaphragm and push rod 85, the O ring alternately passes over the pivot41, thereby causing the valve cover 39 to pivot in the manner previouslydescribed. Positive initiation of valve cover movement is afforded by anupper flipper 92 and a lower flipper 93. The flippers are mounted onpivots 94, 95. Each flipper includes a respective arm 96, 97 whichextends into the path of pin 88. As the pin 88 moves alternately to theupper and lower limit of its stroke, it contacts the respective flipperarm which pivots, giving the initial impetus to rotation of the valvecover 39.

FIGS. 3 and 5 also illustrate some modifications to the liquid pumpportion. The piston shaft 98 is secured to a solid piston 99. The lowerchamber 60' of pump cylinder 80 communicates with pumping chamber 47 byan opening 100 closed by a valve disc 101 mounted on a leaf spring102..The pumping cylinder 80 defines two ports 103, 104 which communicate with the upper pumping chamber 46'. It also defines two lower ports105, 106. Port 105 communicates with chamber 60' while port 106communicates with lower pumping chamber 47'. As will be seen mostclearly in FIG. 5,

ports 104, 106 are closed, respectively, by valve discs 107, 108 mountedon leaf springs 109, 110, secured to a common spring mount 1 l 1. Port103 is open, but port 105 is also closed by a valve disc 112 on a leafspring 113 supported by spring mount 114. Positioned atop the four portsis a manifold cover 115 having a central wall 116 forming one fluidcharmel interconnecting ports 104, 106 and another fluid channelinterconnecting ports 103, 105.

The operation of the liquid pumping portion will now be explained byassuming that the pumping chambers and manifold are filled with thefluid to be pumped. As piston 99 rises, the liquid in the upper chamber46' pushes open valve disc 107, causing liquid to flow into the manifoldand out the delivery hose 76'. Ports 105, 106 remainclosed by therespective valve discs 112, 108. The suction created in lower chamber47' permits the fluid in chamber 60 to raise the valve disc 101 ofi itsseat, allowing the pumped liquid to fill the lower chamber.

On the downstroke, the fluid in chamber 47' is expelled through port106, lifting valve disc 108 so as to pressure operation. It comprises ahousing 117 and a cover plate118 enclosing toggle valve 82. Highpressure air is supplied from a supply line 119 through a bushing 120.Mounted on the inside of cover plate. 118, by means of a screw 121 and'aspacer 122, is a spring 123. Spring 123 is drilled at approximately itsmidpoint where it supports a rubber or plastic valve disc 124 whichrests against and closes the end of bushing 102. Theright end'of coverplate 118 defines a circular opening 125 closed by a resilient diaphragm126 secured by a retaining ring 127 and screws 128. The diaphragm isinterconnected with the end of spring 123 by means of a cap screw 129,bushing 130, nut 131, and washers 132.

In operation, air from the compressor forces the valve disc 124 offitsseat and it enters the housing 117, passing through the open port oftoggle valve 82 to one side of the motor diaphragm. The opposite side ofthe motor diaphragm is open to atmosphere through the channel in valvecover 39'. If pressure within housing 117 exceeds a pre-selected value,it forces the diaphragm 126 outwardly which pulls the end of the spring123 with it.- This causes valve disc 124 to seat against bushing 120 andcut off the air supply.

While the invention has been described with particular application tothe pumping of cumbustible liquid fuels for use in internal combustionengines, it will be understood that the portable liquid pump of theinvention may be employed as well for pumping from reservoirs of otherliquids, such as water for example. Also, it is to be understood thatthe invention may be powered either by connection to a source of vacuumor utilized with equal efircacy by connection to a source of compressedair, or other gases at a pressure greater than atmospheric pressure. Theinvention is thus a portable liquid pump powered by an integral motorcapable of being driven by differential gas pressures.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the above construction withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention which,as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

- 1. A double acting liquid fuel pump of the reciprocating piston typecomprising in combination:

A. a liquid pumping chamber comprising first and second sealedcompartments separated by a first piston slidably movable therebetween,

B. A vacuum chamber comprising first and second hermetically sealedcompartments separated by a second piston movable therebetween,

C. a linearly reciprocable piston shaft common to said first and secondpistons, and having one end thereof extending through a wall of saidfirst sealed vacuum compartment,

D. first valve means connected to and operable by said extending pistonshaft end, and movable between first and second operating positions,

1. means on said valve for connection thereof to a vacuum line,

2. means connecting said valve when in a first position to said firstvacuum compartment,

3. further means connecting said valve in its second position to saidsecond vacuum compartmerit,

E. first and second liquid release valves in said first and secondliquid pumping compartments on opposite sides of said first piston,

1. each of said release valves spring loaded into closed position butoperable to open under the application of liquid pressure, 7

2. both of said liquid release valves connecting with a common liquidoutlet port,

F. a liquid intake chamber having means for connection thereof to areservoir of liquid,

G. first and second liquid check valves connected with said liquidintake chamber,

1. said first check valve mounted in said first piston and connectingsaid intake chamber with said first compartment of said liquid pumpingchamber, and

2. said second check valve connecting said intake chamber with saidsecond compartment of said liquid pumping chamber,

whereby upon movement of said first piston in a direction to decreasethe volume of said first liquid compartment and increase the volume ofsaid second liquid compartment said second check valve opens to admitliquid from said intake chamber into said second compartment, and uponmotion of said first piston in the opposite direction said first checkvalve opens to admit liquid from said intake chamber into said firstcompartment.

.2. The combination of claim 1 wherein said second piston comprises aflexible diaphragm centrally mounted between symmetrically opposed wallsof said vacuum chamber.

3. The combination of claim 1 wherein said first valve means comprises atoggle valve connected by a flexible linkage to the extending end ofsaid reciprocable piston shaft.

4. The combination of claim 3 wherein said toggle valve vacuumconnecting means includes a flexible hose connectable to the vacuum lineof an internal combustion engine.

5. A vacuum powered liquid pump comprising in combination A. ahermetically sealed vacuum chamber having a pair of symmetricallyopposed walls,

1. a flexible diaphragm piston centrally mounted within said vacuumchamber between said opposed walls,

B. a linearly reciprocating piston shaft connected to the center of saidflexible diaphragm piston and having opposite ends thereof extendingthrough centrally aligned sealed openings in said opposed vacuum chamberwalls,

1. first valve means connected with and operable by one extending end ofsaid piston shaft for alternately applying a vacuum to opposite sides ofsaid flexible diaphragm piston to cause reciprocal movement thereofbetween said opposed vacuum chamber walls,

a. means connecting said valve means to a source of vacuum,

C. a dual compartment liquid pumping chamber having first and secondliquid receiving compartments coaxially aligned with the other end ofsaid reciprocating piston shaft and having a sealed linear bearing in afirst wall thereof receiving and supporting said other end of saidpiston shaft within said liquid pumping chamber,

D. a second piston mounted on said other extending end of said pistonshaft within the first compart ment of said liquid pumping chamber andreciprocably movable between said first wall and an opposite second wallforming said first compartment of said pumping chamber,

1. the movement of said second piston being in synchronism with movementof said flexible diaphragm piston,

2. a first liquid entrance valve on said second piston normally openwhen said piston is moved in a first direction and closed when saidpiston is moved in a second and opposite direction,

3. a second liquid entrance valve on said second liquid chamber wallnormally closed when said piston is moved in said first direction andopened when said piston is moved in said second direction,

a. said second liquid entrance valve connecting said first and secondcompartments of said liquid pumping chamber,

. first and second liquid exit valves in said liquid pumping chamber onopposite sides of said second piston,

a. said first exit valve normally closed and said second exit valvenormally open when said piston is moved in said first direction b. saidfirst exit valve normally open and said second exit valve normallyclosed when said piston is moved in said second direction,

c. a common passageway in said pump connecting both said first andsecond liquid exit valves with a single exit port, and

E. an entrance port of said pump connected with said second compartmentof said pumping chamber and adapted for connection to a liquidreservoir.

6. The combination of claim 5 wherein said first valve means comprises atoggle valve having first, second and third ports, and said toggle valveis movable by said reciprocating piston shaft between first and secondpositions alternately connecting said third port to said first andsecond ports.

screw into a threaded oil drum bung hole, and a flat surface formed onsaid external threaded portion to provide an air vent to said drumthrough said bung hole.

8. A double acting liquid fuel pump of the reciprocating piston typecomprising:

A. a liquid pumping chamber comprising first and second sealed liquidcompartments separated by a first piston slidably movable therebetween;

B. a gas motor chamber comprising first and second hermetically sealedgas compartments separated by a second piston movable therebetween;

C. a linearly reciprocable piston shaft common to said first and secondpistons;

D. first valve means operable by said second piston and movable betweenfirst and second operating positions,

1. means on said valve for connection thereof to a gas line,

2. means connecting said valve when in a first position to said firstgas compartment,

3. further means connecting said valve in its second position to saidsecond gas compartment,

4. push rod means remote and separate from said piston shaft connectingsaid second piston to said valve;

E. first and second liquid release valves respectively in said first andsecond liquid pumping compartments,

1. each of said release valves spring loaded into closed position butoperable to open under the application of liquid pressure,

2. both of said liquid release valves connecting with a common liquidoutlet port;

F. a liquid intake chamber having means for connectionthereof to areservoir of liquid;

G. first and second liquid check valves connected with said liquidintake chamber,

1. said first check valve connecting said intake chamber with said firstliquid compartment, and

2. said second check valve connecting said intake chamber with saidsecond liquid compartment,

whereby, upon movement of said first piston in a direction to decreasethe volume of said first liquid compartment and increase the volume ofsaid second liquid compartment, said second check valve opens to admitliquid from said intake chamber into said second compartment, and uponmotion of said first piston in the opposite direction said first checkvalve means opens to admit liquid from said intake chamber into saidfirst compartment.

9. The pump of claim 8 wherein saidsecond piston comprises a flexiblediaphragm centrally mounted between symmetrically opposed walls of saidgas chamber. 7

10. The pump of claim 9 wherein said first valve means comprises atoggle valve connected by a push rod to said flexible diaphragm.

11. The pump of claim 10 wherein said toggle valve has first, second,and third ports and is movable by said push rod between first and secondpositions alternately connecting said third port to said first andsecond ports.

12. The pump of claim 8 wherein the means for connecting said firstvalve to a gas line comprises a pressure regulator connectable to acompressed air source.

13. The pump of claim 12 wherein said pressure regulator comprises: anenclosure surrounding said valve; an inlet check valve in saidenclosure; and means for resiliently loading said check valve toward itsclosed position.

14. The pump of claim 13 wherein said loading means comprises: acantilevered spring within said enclosure; a diaphragm secured to theunsupported end of said spring and mounted in an opening defined by saidenclosure; and a closure member for said check valve supported by saidspring intermediate its ends.

2% UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTWN Patent No. 3 I700 .359 Dated t b 2g 1 312 Inventor(g) John A. Vanderjagt It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Title Page: Correct assignee to read c ien co, Ine

2, line 48 "strike" should be stroke-.

Signed and sealed this 10th day of April 1973 (SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents

1. A double acting liquid fuel pump of the reciprocating piston typecomprising in combination: A. a liquid pumping chamber comprising firstand second sealed compartments separated by a first piston slidablymovable therebetween, B. A vacuum chamber comprising first and secondhermetically sealed compartments separated by a second piston movabletherebetween, C. a linearly reciprocable piston shaft common to saidfirst and second pistons, and having one end thereof extending through awall of said first sealed vacuum compartment, D. first valve meansconnected to and operable by said extending piston shaft end, andmovable between first and second operating positions,
 1. means on saidvalve for connection thereof to a vacuum line,
 2. means connecting saidvalve when in a first position to said first vacuum compartment, 3.further means connecting said valve in its second position to saidsecond vacuum compartment, E. first and second liquid release valves insaid first and second liquid pumping compartments on opposite sides ofsaid first piston,
 1. each of said release valves spring loaded intoclosed position but operable to open under the application of liquidpressure,
 2. both of said liquid release valves connecting with a commonliquid outlet port, F. a liquid intake chamber having means forconnection thereof to a reservoir of liquid, G. first and second liquidcheck valves connected with said liquid intake chamber,
 1. said firstcheck valve mounted in said first piston and connecting said intakechamber with said first compartment of said liquid pumping chamber, and2. said second check valve connecting said intake chamber with saidsecond compartment of said liquid pumping chamber, whereby upon movementof said first piston in a direction to decrease the volume of said firstliquid compartment and increase the volume of said second liquidcompartment said second check valve opens to admit liquid from saidintake chamber into said second compartment, and upon motion of saidfirst piston in the opposite direction said first check valve opens toadmit liquid from said intake chamber into said first compartment. 2.means connecting said valve when in a first position to said firstvacuum compartment,
 2. means connecting said valve when in a firstposition to said first gas compartment,
 2. both of said liquid releasevalves connecting with a common liquid outlet port, F. a liquid intakechamber having means for connection thereof to a reservoir of liquid, G.first and second liquid check valves connected with said liquid intakechamber,
 2. said second check valve connecting said intake chamber withsaid second compartment of said liquid pumping chamber, whereby uponmovement of said first piston in a direction to decrease the volume ofsaid first liquid compartment and increase the volume of said secondliquid compartment said second check valve opens to admit liquid fromsaid intake chamber into said second compartment, and upon motion ofsaid first piston in the opposite direction said first check valve opensto admit liquid from said intake chamber into said first compartment. 2.The combination of claim 1 wherein said second piston comprises aflexible diaphragm centrally mounted between symmetrically opposed wallsof said vacuum chamber.
 2. a first liquid entrance valve on said secondpiston normally open when said piston is moved in a first direction andclosed when said piston is moved in a second and opposite direction, 2.both of said liquid release valves connecting with a common liquidoutlet port; F. a liquid intake chamber having means for connectionthereof to a reservoir of liquid; G. first and second liquid checkvalves connected with said liquid intake chamber,
 2. said second checkvalve connecting said intake chamber with said second liquidcompartment, whereby, upon movement of said first piston in a directionto decrease the volume of said first liquid compartment and increase thevolume of said second liquid compartment, said second check valve opensto admit liquid from said intake chamber into said second compartment,and upon motion of said first piston in the opposite direction saidfirst check valve means opens to admit liquid from said intake chamberinto said first compartment.
 3. a second liquid entrance valve on saidsecond liquid chamber wall normally closed when said piston is moved insaid first direction and opened when said piston is moved in said seconddirection, a. said second liquid entrance valve connecting said firstand second compartments of said liquid pumping chamber,
 3. Thecombination of claim 1 wherein said first valve means comprises a togglevalve connected by a flexible linkage to the extending end of saidreciprocable piston shaft.
 3. further means connecting said valve in itssecond position to said second gas compartment,
 3. further meansconnecting said valve in its second position to said second vacuumcompartment, E. first and second liquid release valves in said first andsecond liquid pumping compartments on opposite sides of said firstpiston,
 4. push rod means remote and separate from said piston shaftconnecting said second piston to said valve; E. first and second liquidrelease valves respectively in said first and second liquid pumpingcompartments,
 4. The combination of claim 3 wherein said toggle valvevacuum connecting means includes a flexible hose connectable to thevacuum line of an internal combustion engine.
 4. first and second liquidexit valves in said liquid pumping chamber on opposite sides of saidsecond piston, a. said first exit valve normally closed and said secondexit valve normally open when said piston is moved in said firstdirection b. said first exit valve normally open and said second exitvalve normally closed when said piston is moved in said seconddirection, c. a common passageway in said pump connecting both saidfirst and second liquid exit valves with a single exit port, and E. anentrance port of said pump connected with said second compartment ofsaid pumping chamber and adapted for connection to a liquid reservoir.5. A vacuum powered liquid pump comprising in combination A. ahermetically sealed vacuum chamber having a pair of symmetricallyopposed walls,
 6. The combination of claim 5 wherein said first valvemeans comprises a toggle valve having first, second and third ports, andsaid toggle valve is movable by said reciprocating piston shaft betweenfirst and second positions alternately connecting said third port tosaid first and second ports.
 7. The combination of claim 5 wherein saidreservoir connecting means comprises an internally and externallythreaded nipple portion, the internally threaded portion being adaptedto receive a threaded pipe end and the externally threaded portion beingadapted to screw into a threaded oil drum bung hole, and a flat surfaceformed on said external threaded portion to provide an air vent to saiddrum through said bung hole.
 8. A double acting liquid fuel pump of thereciprocating piston type comprising: A. a liquid pumping chambercomprising first and second sealed liquid compartments separated by afirst piston slidably movable therebetween; B. a gas motor chambercomprising first and second hermetically sealed gas compartmentsseparated by a second piston movable therebetween; C. a linearlyreciprocable piston shaft common to said first and second pistons; D.first valve means operable by said second piston and movable betweenfirst and second operating positions,
 9. The pump of claim 8 whereinsaid second piston comprises a flexible diaphragm centrally mountedbetween symmetrically opposed walls of said gas chamber.
 10. The pump ofclaim 9 wherein said first valve means comprises a toggle valveconnected by a push rod to said flexible diaphragm.
 11. The pump ofclaim 10 wherein said toggle valve has first, second, and third portsand is movable by said push rod between first and second positionsalternately connecting said third port to said first and second ports.12. The pump of claim 8 wherein the means for connecting said firstvalve to a gas line comprises a pressure regulator connectable to acompressed air source.
 13. The pump of claim 12 wherein said pressureregulator comprises: an enclosure surrounding said valve; an inlet checkvalve in said enclosure; and means for resiliently loading said checkvalve toward its closed position.
 14. The pump of claim 13 wherein saidloading means comprises: a cantilevered spring within said enclosure; adiaphragm secured to the unsupported end of said spring and mounted inan opening defined by said enclosure; and a closure member for saidcheck valve supported by said spring intermediate its ends.